With sales of Maruti Suzuki's popular diesel models Swift, Dzire and Ertiga dipping together for the first time in May, the carmaker has decided to push volumes by offering a CNG option for the Ertiga compact MPV.

Priced about R30,000 more than the base petrol model, the CNG Ertiga is expected to be launched by next week in the LXi and VXi trims, but not in the top-end ZXi variant. The development is significant because it will underline a change in strategy for Maruti — so far CNG options have been limited to popular models that only have a petrol variant on sale, and not for those with diesel options. The only exception is the low-volume SX4 sedan, which is available with all three fuel options (petrol, diesel and CNG).

“The idea has been to have two fuel options available for every model. Normally, we offer a CNG option only on models that have a petrol as a lot of work is needed to modify the engine and the suspension,” a senior company official told FE. For Maruti, CNG variants are limited to models such as the Alto, Eeco, WagonR and SX4.

The launch of a CNG option follows another volume-boosting move. Last month, Maruti launched the ‘Feliz’ special edition version of the Ertiga, which offers premium trims such as a silver finish on the grille, a rear-parking sensor and body graphics.

Since its launch in April 2012, Ertiga, which is based on the Swift platform, has been a success story for Maruti. It has boosted the company’s utility vehicle volumes with monthly sales of over 5,000 units at a time when other SUV options, such as the Gypsy and the Grand Vitara, found few takers. This was largely because the latter two were available only with petrol engines while demand in the UV segment is limited to diesels. Strong volumes helped Ertiga enter the club of top-10 selling models for passenger vehicles in India, a rare feat for a utility vehicle.

However, with the high base of last year catching up and diesel prices rising, Maruti's UV volumes (which mostly comprise Ertiga) fell 5% in April and 44% in May this year. With other popular diesel models such as the Swift and the Dzire also unable to maintain growth, Maruti's total domestic sales in May fell 13% to 77,821 units.

“What you see are wholesale numbers, but retail sales have not fallen as